Currently, reading of barcodes on containers such as test tubes and similarly shaped vessels oriented in an array requires movement of an element holding the containers far outside the array for reading barcodes on the containers by a barcode reader. Alternatively, the containers themselves are removed far outside of the array for reading barcodes on the containers by a barcode reader. This process is time consuming, requires complex, and consumes an inordinate amount of lab space.
For example, the MICROLAB/AT instrument line has been available for sale for nearly twenty years by the assignee of the present application, and can be purchased with a barcode reading option that requires barcode labeled containers to be lifted up from a rack in a special holder into a reading zone above the rack. Up to twelve tubes may be lifted at one time. A laser type barcode reader is mounted on an X-Y axis system that moves to read barcodes on the barcode labeled containers. This method requires the instrument volume above the rack to be clear and requires a complex lifter mechanism comprised of thirteen motors and a barcode reader comprised of two motors.
Additionally, The MICROLAB STAR instrument line has been available for sale in the USA for approximately eight years by the assignee of the present application, and can also be purchased with a barcode reading option. In this instrument line, barcode labeled containers are loaded in single column racks that are then loaded onto a tray that protrudes from the front main footprint of the instrument. Barcodes are read by engaging a toothed wheel into a corrugated pattern on the underside of the linear rack, and pulling the rack past a stationary barcode reader while a sensor checks for the presence or absence of a barcode labeled container.
Accordingly, when instruments move barcoded containers past a stationary barcode reading element, the required footprint of the instrument, or height of the instrument essentially doubles, requiring space for un-read test tubes and test tubes that have been read and are in final position. If the “waiting to read” position is outside the normal footprint of the instrument, this may constitute a hazard to passing personnel as test tubes are automatically ejected and read. Additionally, robotically manipulating single tubes (pick/carry/read/replace) is very time consuming and requires complex apparatus including special grippers for the tops of tubes, which may be fouled by the samples they contain, leading to cross-contamination. Pushing up test tubes or containers from below for reading requires large amounts of actuation and requires the volume above to be free of obstruction, as well as specialized tube holders that might obscure the bottom of a barcode label, should that label be applied incorrectly.
Furthermore, a hand-held or stationary commercial reader apparatus has been an available option for many years, but accurate tracking and positioning of containers with this type of apparatus becomes the sole responsibility of the user/operator and is error prone and requires laborious operator interaction.
Hence, there is a need to overcome the significant shortcomings of the known prior art as delineated hereinabove.